Sound absorbing and decoupling material such as batts constructed from mineral fibre (rock wool), glass fibre, and polyester are often placed in a space between two dividing panels to absorb incident sound energy and reduce noise transmission from one side of the panel to another. Often the dividing structure is a single panel, and may be a ceiling panel, disposed generally horizontally. It is often the case that a layer of limp, dense material is adhered to one side, often the underside, of the batt, so that the limp layer “floats” on the batt with respect to the panel, providing a barrier to, and much reducing the energy of incident sound waves.
Over time, especially where the panel is a ceiling panel, and also in vertical wall installations, the mass of the limp layer or barrier tears the fibers of the batt away from their hold on each other. The barrier falls away, and any sound energy is subsequently less impeded from passing through the dividing structure. Heavy vibrations generally associated with high sound levels generally accelerate this process.
Also, transmission through dividing structures via structural vibration and reflection of energy from surfaces within an enclosure or space all combine to increase the Leq within the space, causing distractions to users of the space.
The present invention seeks to ameliorate one or more of the abovementioned disadvantages.